Torque based air per cylinder and volumetric efficiency determination

Abstract

A method of regulating operation of an internal combustion engine includes monitoring a manifold absolute pressure (MAP) of the engine, determining an engine torque based on the MAP, estimating an air per cylinder (APC) based on the torque, determining a volumetric efficiency of the engine based on the APC and regulating operation of the engine based on the volumetric efficiency.

1. A method of regulating operation of an internal combustion engine, comprising:
 monitoring a manifold absolute pressure (MAP) of said engine; 
 determining an engine torque based on said MAP; 
 estimating an air per cylinder (APC) based on said torque; 
 determining a volumetric efficiency of said engine based on said APC; and 
 regulating operation of said engine based on said volumetric efficiency. 
 
     
     
       2. The method of  claim 1  wherein operation of said engine is further regulated based on said APC. 
     
     
       3. The method of  claim 1  further comprising:
 determining a correction factor based on an actual APC; and 
 correcting said APC based on said correction factor. 
 
     
     
       4. The method of  claim 3  further comprising determining whether said engine is operating in steady-state, wherein said step of correcting said APC is executed when said engine is operating in steady-state. 
     
     
       5. The method of  claim 1  further comprising monitoring an intake air temperature, wherein said volumetric efficiency is further based on said MAP and said intake air temperature. 
     
     
       6. The method of  claim 1  wherein said step of determining an engine torque includes processing said MAP through a MAP-based torque model. 
     
     
       7. The method of  claim 1  wherein said step of estimating an APC includes processing said engine torque through an inverted APC-based torque model. 
     
     
       8. A system for regulating operation of an internal combustion engine, comprising:
 a first module that determines an engine torque based on a manifold absolute pressure (MAP) of said engine; 
 a second module that estimates an air per cylinder (APC) based on said torque; 
 a third module that determines a volumetric efficiency of said engine based on said APC; and 
 a fourth module that regulates operation of said engine based on said volumetric efficiency. 
 
     
     
       9. The system of  claim 8  further comprising a MAP sensor that monitors a said MAP of said engine. 
     
     
       10. The system of  claim 8  wherein operation of said engine is further regulated based on said APC. 
     
     
       11. The system of  claim 8  further comprising:
 a fifth module that determines a correction factor based on an actual APC; and 
 a sixth module that corrects said APC based on said correction factor. 
 
     
     
       12. The system of  claim 11  further comprising a seventh module that determines whether said engine is operating in steady-state, wherein said sixth module corrects said APC when said engine is operating in steady-state. 
     
     
       13. The system of  claim 8  further comprising a sensor that monitors an intake air temperature, wherein said volumetric efficiency is further based on said MAP and said intake air temperature. 
     
     
       14. The system of  claim 8  wherein said first module determines said engine torque by processing said MAP through a MAP-based torque model. 
     
     
       15. The system of  claim 8  wherein said second module estimates said APC by processing said engine torque through an inverted APC-based torque model. 
     
     
       16. A method of regulating operation of an internal combustion engine, comprising:
 monitoring a manifold absolute pressure (MAP), an actual air per cylinder (APC) and an intake air temperature of said engine; 
 calculating an engine torque based on said MAP by processing said MAP through a MAP-based torque model; 
 calculating an estimated APC based on said torque by processing said engine torque through an inverted APC-based torque model; 
 determining a volumetric efficiency of said engine based on said estimated APC; and 
 regulating operation of said engine based on said volumetric efficiency. 
 
     
     
       17. The method of  claim 16  wherein operation of said engine is further regulated based on said estimated APC. 
     
     
       18. The method of  claim 16  further comprising:
 determining a correction factor based on said actual APC; and 
 correcting said estimated APC based on said correction factor. 
 
     
     
       19. The method of  claim 18  further comprising determining whether said engine is operating in steady-state, wherein said step of correcting said estimated APC is executed when said engine is operating in steady-state. 
     
     
       20. The method of  claim 16  wherein said volumetric efficiency is further based on said MAP and said intake air temperature.